Heating unit



June 9,. 1953 J. E. CHAMBERS ETAL HEATING UNIT Filed Oct. 18, 1948 @Mwog Zi a Patented June 9, 1953 UNITED STATES PATENT OFFICE HEATING UNIT John E. Chambers and Thomas Esta. Phares,

Shelbyville, Ind., assignors to Chambers Corporation, a corporation of Indiana Application October 18, 1948, Serial No. 55,094

12 Claims. l

This invention relates to a heating unit, and particularly to means for maintaining an atmosphere of hot air around a cooking vessel positioned in the unit.

A heating unit in accordance with the present invention is a separate cooking unit which may be built into a gas range and serve as a heating Well, or it may be built as an individual unit without reference to a range.

In the embodiment of the heating unit comprising the present invention, the novel arrangementy of the nues increases the eiciency of the distribution of heat around the cooking vessel. The present invention also contemplates the provision of an inner hull designed to seal a large volume of hot air around the cooking vessel. Another advantage of the present invention resides in the elimination of movable dampers which heretofore have been required to seal the heat Within the heating unit when it was desired to cook with retained heat. The elimination of these dampers gives rise to a further advantage and that is that the unit may be fabricated with fewer parts and in a more facile and less costly manner than heretofore.

The structure by which the above advantages are attained will be described in the following specification, taken in conjunction with the accompanying drawings, in which:

Figure l is a cross sectional view, taken along the line I--I of Fig. 2, showing the interior arrangement of the structure of a heating unit embodying the present invention; and

Fig. 2 is a cross sectional view, taken along the line 2--2 of Fig. l, showing the relative position of the flues, and showing the grate in top elevation.

In the embodiment of the invention illustrated in the drawings the heating unit is shown incorporated as a heating well in a gas range. It is to be understood, of course, that the unit may be built and used as an integral heating device apart from a range, if desired.

In the drawings, the reference numeral 2 indicates the top of a gas range in which the heating unit is housed. A flange 3 in the range top surrounds the opening 4 which forms the open top of the heating unit. Opening II is closed by a double walled cover 5, filled with insulation 6 of rock Wool or similar material. Cover is provided with a circumferential flange 1 which seats on flange 3. Flange 1, the top of which lies in the same plane as the top of cover l5, is approximately as thick as the depth of the recess forming flange 3, so that cover 5 and flange TI are flush `with top` 2 The heating unit, which may be suspended.

from top 2 or otherwise supported within the range, has an outer hull 9 of cylindrical form, and a concentric flue hull lli of slightly smaller diameter fitting inside the outer hull. The space between outer hull `9 and ue hull IIJ is lled with insulation Il of the same type as insulation 6. Outer hull 9 and flue hull In are provided with registering apertures I2 and I3, respectively, near their bottom. A collar I 4, fitting through apertures I2 and I3, and secured thereto in any suitable manner, forms a seat for the mixing bell I5 of the gas burner I6 which is positioned within and substantially centrally .of the unit.

Outer hull 9 is provided with a pair of flue vent openings I1 near its top. These openings are circumferentially aligned and are spaced apart approximately for a purpose hereinafter described. Flue hull I0 is provided with a pair of flue vent openings I8 of the same size as openings II and in registration therewith. A collar or flue I 9 fitting in openings I'I and I8, is secured in each set of openings I 2', IB by frictional engagement or in any other suitable manner.

The bottom closure of outer hull 9 comprises a disk 20 having an upstanding circumferential flange 2I which fits around the bottom edge of hull 9 and is secured thereto as by welding, or by other similar means. If desired, bottom 20 may be integral with hull 9. Disk 2U is provided with a hole 2,2 open to the atmosphere directly under burner l5.

The bottom of ue hull Ill is closed by a disk 23 which 'has a hole 24 in registration with hole 22 in disk 20.. The greater portion of disk 23 rests on disk 2.0., but a portion surrounding hole 24 is upturned to forma lip 25 spaced above hole 22. The holes 22 and .24 are provided in the bot-v tom of the heating unit to allow passage of sec-` ondary air to burner IIi to maintain the flame when the burner is lighted.

The outer edge of disk y23 is secured to the bottom of flue hull I I) in any. suitable manner. As shown in Fig. l., the bottom. edge of flue hull ID terminates a short distance above bottom disk .20 and the circumferential edge of disk 23 is turned up and welded or otherwise secured to the bottom edge portion of iiue hull I il,

Although the bottom structure .described above is preferred because of the increased strength and rigidity it imparts to the heating unit, it is possible to use a single disk as the bottom closure for both outer hull 9 and flue hull I0. In this event the bottom edge of iiue hull I would be extended to lie in the same plane as the bottom edge of outer hull 9 and the bottom disk would be welded or otherwise secured to both hulls. The edge of the single bottom disk would be dished upwardly around hole 22 to form an equivalent of lip 25.

A bottom plate 26 is supported above lip 25 by studs 21 which project through apertures provided in lip 25. Instead of studs, either screws or bolts, having sleeves acting as spacers, may be used to space bottom plate 26 above lip 25. Bottom plate 26 is provided with a central aperture into which a projection 28 depending from the bottom of burner I6 is seated, thereby locating burner I6 and supporting it in predetermined position directly above holes 22 and 24. The interengagement of projection 28 with the aperture in bottom plate 26 also prevents accidental displacement of burner I6 during the assembly of the heating unit.

A plurality of grate lugs 29 is secured to flue hull I0 by means of bolts 30. A spacer 3| is positioned between each lug 29 and iiue hull I0. An inner hull 32, cylindrical in shape, and of smaller diameter than ue hull I0, is positioned within hull I0. Inner hull 32 is of less length than hull I0 and bolts 30, which secure lugs 29 to hull I 0, also pass through inner hull 32 adjacent its bottom edge to hold it in spaced relationship with respect to the ue hull. Each grate lug 29 has a lip 33 projecting inwardly at right angles from its lower edge. Lips 33 extend past the lower edge of inner hull 32 and cooperate to provide a support for a grate 34.

Grate 34 is preferably of cast iron and is heavy enough to aid in the distribution of heat across the bottom of the heating unit. The grate absorbs a considerable amount of heat from burner I6 while the burner is lighted, and dissipates it slowly after the burner is turned off, thereby retaining the heat at the bottom of the cooking area for a substantial period of time after the burner has been turned oi.

Grate 34 comprises an outer disk 35 adapted to rest on lips 33 which project inwardly from grate lugs 29, an inner disk 36, and a plurality of integral radial arms 31 connecting the disks. Disk 36 is provided with a plurality of apertures 38 which facilitate the distribution of heat from burner I6 across the bottom of the cooking vessel positioned in the heating unit. Disk 35 is provided along its outer edge with a plurality of upstanding projections 39 which facilitate positioning of a cooking vessel 40 on grate 34 and hold it properly centered thereon.

The cylindrical wall forming inner hull 32 has a circumferential ange 4I around its top edge. Flange 4I is secured in any suitable manner to the underside of circumferential iiange 3. The lower edge of inner hull 32 is substantially flush with grate 34. When burner I6 is lighted the hot air from the proximity of the burner travels upwardly and lls the spaces around cooking vessel 40 both inside inner hull 32 and between inner hull 32 and ue hull I 0.

As newly heated air rises from burner I6 it forces the previously heated air through iiues I9. Because iiues I9 are approximately 90 apart, most of the air in the space between ue hull I0 and inner hull 32 travels around a considerable portion of the inner hull before it reaches either flue I 9, thereby imparting its heat to this hull. The heated air inside inner hull 32 is forced down under the lower edge of this hull by the pressure of the constantly rising newly heated air before it can be forced through ilues I9. Flues I9 thus provide avenues for constant escape of the hot air and burned gases from burner I 6 while the burner is lighted. This constant circulation of heated air throughout the cooking area results in an even distribution of heat around cooking vessel 40.

When burner I6 is turned off, the hot air in the space immediately adjacent cooking vessel 40 is virtually sealed in by inner hull 32 because the lighter weight of this hot air prevents its displacement by any cooler air that might otherwise pass into the heating unit through openings 22 and 24 in its bottom. The hot air inside inner hull 32 will stay there until it cools sufliciently to be displaced by outside air and caused to travel down and out of the bottom of hull 32. It is obvious that the heat absorbed by grate 34 will be dissipated slowly and this heat will rise in hull 32 and prolong the heating process after burner I6 has been turned off. The capacity of the heating unit to maintain the hot air around cooking vessel 40 enables the user to turn off the gas sooner than would be possible with other constructions, and thereby reduces gas consumption.

Although `we have described a preferred embodiment of our invention in considerable detail, the description is intended to be illustrative. rather than restrictive, as many details may be modied or changed, without departing from the spirit or scope of our invention. Accordingly, We do not desire to be restricted to the exact structure described.

We claim:

1. A heating unit comprising a pair of concentric imperforate hulls and a pair of flues extending through said hulls adjacent the top edge of said heating unit, an inner hull depending from the top of said heating unit inside said two rst mentioned hulls, said inner hull being shorter than said two rst mentioned hulls and having an imperforate cylindrical wall cooperating with the innermost of said first mentioned pair of hulls to form an insulating space closed at the top and open at the bottom, said inner hull delining a space in whi-ch a cooking vessel is adapted to be placed, and an insulated removable cover flush with the top of said heating unit cooperating with said inner hull to close the top of said space in which the cooking vessel is placed.

2. A heating unit comprising an outer imperforate hull, an imperforate iiue hull positioned within said outer hull in spaced relationship thereto, an inner hull comprising an imperforate wall of less length than either of said two iirst mentioned hulls, 'said inner hull depending inside said iiue hull from the top of said heat; ing unit, said inner hull having an open bottom, a grate supported inside said iiue hull directly under the open bottom of said inner hull, a gas burner positioned under said grate, said inner hull cooperating with said imperforate flue hull to form an insulating space closed at the top and open at the bottom in which air heated by said gas burner moves upwardly and is trapped, and a plurality of ues extending through said nocaut 'outer and nue hulls in a piane above theA bottom of said inner hull.

3f. A heating unit comprising an outer' imperforate hull, an' imperforate flue hull: positioned Within said outer hull in spacedrelationship thereto, an inner hul-l comprising an imperiorate wall of less lengththa'n either of said two rst mentioned hull-'s and defining a space in which a cooking vessel is adapted to be placed, an insulated removable cover flush with the top of said heating unit cooperating with said inner hull to close the top of said space in which the cooking Vessel is placed, said inner hull depending inside said flue hullr from the top of said heating unfit, said inner hull havingan open bottom', a grate. supported inside4V said ilue hull directly under the open bottom: vof said inner hull, said` outer and flue hulls having'a bottom wall provided with a centrally disposed opening, a gas burner positioned above said centrally disposed opening and under said. girate, said inner hull cooperating with said imperoirate flue hull to form an insulating space closed at the top and open at the bottomv in which heated air moving upwardly from the gas burner is trapped, and a pair of nues extending through said outer and nue hulls in a plane above the bottom of said inner hull, said ues being spaced apart approximately 90.

4. A heating unit comprising an outer hull, a due hull positioned within said outer hull, a pair of iiues extending through both of said hulls adjacent the top of said heating unit, a bottom wall having a centrally disposed opening therein, an inner hull having imperforate side walls of less length than said outer hull, said inner hull having an open bottom and being secured adjacent to the top of said heating unit, said inner hull being positioned inside said ue hull and defining a space in which a cooking vessel is adapted to be placed, an insulated removable cover cooperating with the top of said inner hull to close the top of said space in which the cooking vessel is placed, and a gas burner positioned inside said heating unit above said centrally disposed opening and under the open bottom of said inner hull, said inner hull cooperating with said flue hull to form an insulating space closed at the top and open at the bottom, said insulating space surrounding said space in which the cooking vessel is placed and being adapted to receive and retain air heated by said gas burner.

5. A heating unit comprising a cylindrical outer hull, a concentric cylindrical ue hull positioned inside said outer hull, a plurality of grate lugs spaced circumferentially around the inside surface of said flue hull above the bottom thereof, a spacer positioned between each of said grate lugs and said flue hull, an inner hull comprising a cylindrical wall having its lower edge portion engaging said grate lugs, means extending through said inner hull, grate lugs and spacers, to secure the lower edge portion of said inner hull and said grate lugs in spaced relation to said flue hull, and a grate supported on said lugs.

6. A heating unit comprising a cylindrical outer hull, a concentric cylindrical flue hull positioned inside said outer hull, a plurality of grate lugs secured in spaced relationship to the inside surface of said ue hull, an open bottom inner hull having its lower edge secured to said grate lugs, a grate supported on said lugs directly under said inner hull, said inner hull dening a space in which a cooking vessel is adapted to be placed, and an insulated removable cover ilush 6 with the top of said heating unit cooperating with the top edge of said inner hull to closev said space.

'7. In a gas range, a heating unit comprising an outer i'mperforate hull, an imperfor-ate flue hull positioned within said outer hull in spaced relationship thereto, an inner hull comprising an imperforate wall of less length than either of sai-d' two first mentioned hulls, said inner hull depending inside said nue hull from the top of said heating unit, said inner hull having an open bottom, a grate supported inside said flue hull directly under the open bottom of said inner hull, a gas .burner positioned under said grate, said inner hull cooperating with said llue hull to form an insulating space closed at its top and open atA its bottom to receive and retain airv heated by said gas burner, and a plurality of flues extending through said outer and flue hulls in a plane above the bottom of said inner hull.

8. In a gas rang-e, a heating unit comprising a cylindrical outer hull, a concentric cylindrical flue hull positioned inside said outer hull, a plurality of grate lugs spaced circumferentially around the inside surface of said nue hull above the bottom thereof, a spacer positioned between each oi said grate lugs and said nue hull, an inner hull comprising a cylindrical wall having its lower edge portion engaging said grate lugs, means extending through said inner hull, grate lugs and spacers, to secure the lower edge portion of said inner hull and said grate lugs in spaced relation to said flue hull, and a grate supported on said lugs.

9. In a gas range, a top wall having a circular opening, a circumferential ange projecting inwardly around said opening, an outer hull comprising a cylindrical wall secured at its top to the underside of said range top in spaced relationship to said circular opening, a flue hull positioned within said outer hull, an apertured disk secured to the bottom edge of at least `one of said hulls, insulating material interposed between said hulls, a gas burner positioned above said apertured disk, a grate positioned above said gas burner, a pair of ues extending through said hulls adjacent thelitop, an inner hull comprising an imperforate cylindrical wall having its top edge secured to the underside of said range adjacent said opening and its bottom edge terminating adjacent said grate, means holding the bottom edge of said inner hull in spaced relationship to said first mentioned hulls, and an insulated cover having a circumferential flange seating on said first mentioned flange, said insulated cover being flush with the top wall of said range.

10. In a gas range, a top wall having a circular opening, an outer hull comprising a cylindrical wall secured at its top to the underside of said range top in spaced relationship to said circular opening, a flue hull positioned within said outer hull, a pair of flues extending through said hulls adjacent their top, an inner hull comprising an imperforate cylindrical wall having its top edge secured to the underside of said range adjacent said opening and its bottom edge terminating above the bottoms of said other hulls, said inner hull cooperating with said flue hull to form an insulating space closed at its top and open at its bottom, and an insulated cover closing the top of said heating unit.

11. In a gas range, a top wall having a circular opening, an outer hull comprising a cylindrical wall secured at its top to the underside of said range top in spaced relationship to' said circular opening, a flue hull positioned within said outer hull, an apertured disk secured to the bottom edge of at least one of said hulls, insulating material interposed between said hulls, a gas burner positioned above said apertured disk, a grate positioned above said gas burner, a pair of fiues extending through said hulls adjacent their top, an inner hull comprising an imperforate cylindrical wall having its top edge secured to the underside of said range adjacent said opening and its bottom edge terminating adjacent said grate, and an insulated cover closing said circular opening, said inner hull defining an open bottom space under said cover in which a cooking vessel is adapted to be placed, and cooperating with said flue hull to form an insulating space surrounding said space in which said cooking vessel is placed, said insulating space being closed at its top and open at its bottom to receive and retain air heated by said gas burner.

12. A heating unit comprising a pair of concentric imperiorate hulls, the inner hull of said pair of hulls dening a space in which a cooking vessel is adapted to be placed, and said pair of hulls cooperating with each other to form an insulating space surrounding said space in which the cooking vessel is placed, said insulating space being closed at the top and open at the bottom whereby a. large volume of heated air introduced into said insulating space is sealed therein, and a pair of flues extending through said outer hull adjacent the top edge of said heating unit, said flues being spaced apart approximately 90.

JOHN E. CHAMBERS. THOMAS ESTA PHARES.

References Cited in the file of this patent UNITED STATES PATENTS 

